Medical devices, such as endoscopes or other suitable introduction devices, are employed for a variety of diagnostic and surgical procedures, such as laparoscopy, arthroscopy, gynoscopy, thoracoscopy, and cystoscopy, etc. Many of these procedures are carried out for purposes of tissue resection, which generally includes removal of tissue of an organ or a gland to treat tumors, infestations, and the like. In particular, such procedures may be carried out by inserting an introduction device into a patient's body through a surgical incision, or via a natural anatomical orifice (e.g., mouth, vagina, or rectum), and performing the procedure or operation.
Snare devices, in particular, have been used in many medical procedures, including Endoscopic Mucosal Resection (EMR) and Endoscopic Sub-mucosal Resection (ESR), Polypectomy, Mucosectomy, etc., for resecting tissue from a target site. A snare device generally includes a snare loop formed by snare wires, which engages the tissue intended to be resected. The snare loop is controlled and operated at a proximal end of the device through a suitable actuating mechanism. However, in many conventional snare devices, the snare loop has a tendency to twist about itself, away from a plane of a layer of tissue, which may reduce the snare's ability to ensnare the desired tissue.